The individual researcin projects comprising this Endometrial Cancer SPORE require the procurement, processing, and microscopic analysis of normal endometrial tissues and endometrial cancers from surgical hysterectomy specimens. In addition, several of the SPORE projects propose animal model studies that will require histological processing and careful pathological assessment of rat and mouse uterine tissues. In this proposal, the Core will continue its active commitment to high-quality translational research in endometrial cancer that began with initial SPORE funding in 2003. Since 2003, the Gore has provided endometrial tissues and pathological expertise to 20 different investigators, 9 of which were outside of MDACC. These collaborations beginning in 2003 have resulted in 57 publications and 2 NIH/NCI R01 grants in which Core materials from endometrial cancer patients were used. Importantly, the Core enthusiastically supports trainees in learning translational research; 23 different trainees (9 different trainee mentors) have been provided with Core resources and expertise since 2003. The following Specific Aims are proposed for this Core. Aim 1 is to maintain a frozen and paraffinembedded tissue repository of endometrial cancers, hyperplasias, and normal endometrial samples. Aim 2 is to provide pathological review for all clinical specimens utilized in the SPORE projects and for related clinical trials and to provide histopathological technical services as necessary. This includes histological processing and microscopic evaluation of uterine tissues derived from the proposed mouse and rat experiments in several projects. Aim 3 is to establish a blood/urine/ascites fluid collection from patients undergoing hysterectomy for endometrial cancer and endometrial hyperplasia and from patients undergoing hysterectomy for non-endometrial pathology (uterine leiomyomas, cervix dysplasia, endometriosis). Such fluids will provide resources for the future testing of putative diagnostic/prognostic markers for endometrial cancer. Aim 4 is to create and maintain a database for all frozen and paraffin-embedded endometrial tissues and fluids collected by the Core.